1080TI windows 10
2.80, 2018-11-29 15:57, 26d5a3625ed Blender 2.8 Beta
When using a displace modifier with a texture such as clouds, changing the texture properties (i.e size) does not cause an update in the viewport.
Open a new file.
Add a plane.
Add a displace modifier.
Add a cloud texture to this.
Change the size of the cloud texture, observe viewport.